Vice Adm. W. P. Lawrence, POW and Naval Academy head

Vice Adm. William Porter Lawrence, a Vietnam prisoner of war, former U.S. Naval Academy superintendent and father of an astronaut, died of natural causes Friday at his home in Crownsville. He was 75.

Admiral Lawrence had an illustrious 34-year career in the Navy, beginning as a test pilot after he graduated from the Naval Academy and ending as the deputy chief of naval operations.

But he was most famous for his perseverance during six years as an American POW during the Vietnam War, when he endured torture at the hands of the North Vietnamese.

"He's probably the greatest man I've ever known in my life," said Arizona Sen. John McCain, who spent almost six years with Lawrence in the infamous Hanoi Hilton prison. "It was his constant, steadfast, inspirational, yet very rational leadership that guided many of us through some very difficult times."

Admiral Lawrence was born in Nashville, Tenn., on Jan. 13, 1930. As a young man, he excelled academically and athletically, standing out as a football, basketball and baseball player at West End High School. He turned down a scholarship to Yale University to attend the Naval Academy, where he played all three sports, was elected class president, rose to the rank of brigade commander -- the highest-ranking midshipman -- and finished eighth academically in a graduating class of 725.

Together with H. Ross Perot, the Dallas billionaire and two-time presidential candidate, he helped develop the academy's Honor Concept, which allowed midshipmen to police themselves for conduct such as cheating.

"We went from platoon to platoon, and when Admiral Lawrence finished, the honor code belonged to the midshipmen, and it set the highest possible standard for integrity," Perot said.

Admiral Lawrence became a Navy test pilot after graduating, an elite and dangerous assignment where pilots must push new jets to their extremes. He also came just short of being in the nation's first group of astronauts, along with friends Alan Shepard and John Glenn. He was dropped from consideration when doctors found a heart murmur.

On June 28, 1967, he was shot down over North Vietnam and taken to the notorious Hoa Lo prison, nicknamed "Hanoi Hilton" by POWs, where he was routinely tortured. He was strung up to pipes and bent into positions that he said caused the flesh to be "literally stripped from my ankles from writhing in the irons." He was burned with cigarettes. He was stuffed into a 6-square-foot hole with no light, where he fought rats for food and developed heat sores from the high temperatures.

Once, when a high-ranking general was being punished for organizing a religious meeting, Admiral Lawrence led the POWs in singing "The Star-Spangled Banner."

"He encouraged and sustained those of us who needed it and never seemed to need it himself," said McCain, who was in a cell next to Admiral Lawrence and often communicated with him by tapping the walls and sweeping the floor in patterns.

To pass the time, he recalled very specific details from his life and wrote poetry, penning in iambic pentameter what later became Tennessee's official state poem.

When he came home in 1973, he found that his wife had left him to marry an Episcopal clergyman. The next year, he married Diane Wilcox Rauch, a physical therapist, and moved to California.

From 1978 to 1981, he served as the superintendent of the Naval Academy, where he helped smooth the way for women entering the academy and was on hand for his daughter Wendy's graduation in 1981. She went on to become an astronaut, and friends said it delighted him that she made it.

He went on to command the U.S. 3rd Fleet in Hawaii and was deputy chief of naval operations when he retired in 1986. He won the Distinguished Service Medal four times, three Silver Stars, the Legion of Merit, the Distinguished Flying Cross, the Bronze Star with "V" device and two Purple Hearts.

Funeral services will be held at 11 a.m. Dec. 14 at the Naval Academy Chapel. Shuttle services to the academy from Navy-Marine Corps Memorial Stadium will begin at 9:30 a.m.

In addition to his wife, Admiral Lawrence is survived by three children, Capt. Wendy Lawrence of Houston, William Lawrence Jr. of Yorba Linda, Calif., and Dr. Laurie Lawrence of Nashville; a stepson, Frederick Rauch of North Stonington, Conn.; and five grandchildren.